CVE-2026-78847: n/a
A vulnerability in the gray-matter library allows arbitrary code execution via the use of eval() in its JavaScript engine when parsing front matter with the language set to js/javascript. This affects all versions, including 4.0.3. The issue arises from unsafe evaluation of code, leading to potential execution of malicious scripts.
AI Analysis
Technical Summary
The gray-matter library contains a security flaw in its lib/engines.js component where the JavaScript engine uses eval() to parse front matter when the language is specified as js or javascript. This unsafe use of eval() enables an attacker to execute arbitrary code within the context of the application using gray-matter. The vulnerability has been verified on version 4.0.3 and is reported to affect all versions of the library.
Potential Impact
Successful exploitation of this vulnerability allows an attacker to execute arbitrary JavaScript code on the host environment where gray-matter is used. This can lead to full compromise of the application or system depending on the execution context and privileges of the affected process.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid processing untrusted input with gray-matter when using the js/javascript language option in front matter parsing. Consider disabling or restricting this feature if possible.
CVE-2026-78847: n/a
Description
A vulnerability in the gray-matter library allows arbitrary code execution via the use of eval() in its JavaScript engine when parsing front matter with the language set to js/javascript. This affects all versions, including 4.0.3. The issue arises from unsafe evaluation of code, leading to potential execution of malicious scripts.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The gray-matter library contains a security flaw in its lib/engines.js component where the JavaScript engine uses eval() to parse front matter when the language is specified as js or javascript. This unsafe use of eval() enables an attacker to execute arbitrary code within the context of the application using gray-matter. The vulnerability has been verified on version 4.0.3 and is reported to affect all versions of the library.
Potential Impact
Successful exploitation of this vulnerability allows an attacker to execute arbitrary JavaScript code on the host environment where gray-matter is used. This can lead to full compromise of the application or system depending on the execution context and privileges of the affected process.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid processing untrusted input with gray-matter when using the js/javascript language option in front matter parsing. Consider disabling or restricting this feature if possible.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2026-08-25T00:00:00.000Z
- State
- PUBLISHED
Threat ID: 6ab1abba55bf5e2cf58b4671
Added to database: 09/21/2026, 22:12:10 UTC
Last enriched: 09/21/2026, 22:13:02 UTC
Last updated: 09/22/2026, 00:44:35 UTC
Views: 6
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